Pot type oil burner and low fire pilot unit



Jan. l5, 1957 Q B, RlCHARDsON l j 2,777,511

POT TYPE OIE BURNER AND LOW FIRE PILOT UNIT Filed March 24, 1955 United States Patent P-OT TYPE GIL LOWFPILOI` t f T Carl B. Richardson, Norfolk, Va.

Application March 24,1953., Serial No.l 344,352

` 3 Claims. '(Cl. 15S-91) This invention relates lgenerally'tothe class offuel` oil #burners and is directed particularly' tWimprOVements 'in 'possible with 'the' ordinary pot type burner 'and'bymeans Yof which the iireinthe pot may be easily `raised to full fuel consumption.

Still another-object of the invention is ,toprovide'ap'ot type oilburner having yan inside secondaryor 'pilot'burner in which a lowhaine-may ybe 'maintained and 'from' 'which ffuel 'run' into the potv may'lbe ignited vfor `full fuel for-high fire operation.

v'-Still another yobiecthofithe invention` is "to provide apot type burner 'having' Aa pilot burner' -as--above set fotth, with novel means lfor conducting combustion i thereby maintaining lair directly to the pilot burner through *the -largerfburnerorpo from the Lsameairisource as `that V'-fifomi#which the pot `isfsuppl-ied. p

O-ther objects andy advantages ofl the inventioneiitilltbeleoine-apparent-as ythe descriptionfofthef'fsame proceeds, Landistheinvention' -`'uv-ill xberbest understood froml a considlerationf'fof it-he following detail'edfdescription vItalien "".i-n ot'n-inection with-the accompanying drawings for-mingle part of the-speeiiieation,l with ltil-1e understanding; however, lthatfthelinvention-is not .to be limited to'ithelexactdetails of construction shown fanddescribedf-siuceobviousmodifcationsiwvifllv-.occur `to, ai person skilledai-n theiart.

i flnthe drawings:

Figure lizisza' Verticalsectional'yiewthrough a' lpot type `)burner constructed in accordance Withl the present .invenltion.sl-'iovvings:the: novel pilotburnertherein.

Figure 2 is'a View in top plan .of thelpilotlburnentperzse.

'Figure 35i-sa :vertical :sectionalview taken'fsubstantialtly zon the linei-S'offligure 2.

Figure-4 is l:afplan 4view yolffthe 'insidefzof :tbebottomiof lthe `pot lookin-g down` Lupon the' burner A:and showingnthe fignitin'g wick.

' `Referring now :more particularly :to tlaednawings the Ilnumeral f1@ generally designates kan iairxhousingainwxvhich a :static air pressure vis' maintained -in accordance with customary practice, ythe air being applied vfromr:ar-suitable source suchas an pump or the like., notishown; through :the :pipe csr-conduit l1-Which 4opens through 'therside 4viali `vofthe housing llt) yas illustrated.

The ,pot :burner unit yconstructed in accordancerv/ith.the present invention isl generally .designated .12. ...This Aburner Acomprises the bottom pan or receptacle 13 Vvvbichrirt accordance with the present Ainvent-ion, has. a bottom wall 14 anda low side wall 15y formed ofthick or heavy cast iron 'or' steel. lForming a continuationof the low thick Aor heavywall 15 is'the 'thinner circular wall"16"which 'is 2,777,511 Patentedjan. 1,5,7 1957 2 'formedof "lightweight sheet 'steel and which eucir'cles the top edg'e 'ofl the 1ow`wall`1`5 and is secured theretoina suitable manner kas,k for example,f bythe-use of screws 17 .or ithe' like.

The'walll is provided with numerousair admission y'apertures 18 whereby air' may'e'nterfrom-'ithe housing 10, the overall diameter'ofthe'w'all 16 being materiallyjless lthan the vinside diameterof'the housing 10 as shown Wherebyspace `ispro,vided around'the pot for'free movement of" air..

y"The top *of the pot is elosed bythe head plate "19 which 'isjprovided Withthe'dependingannular flange 201 which "ts' withintheWal-llfto which itis secured in a'suitable manner by the empioymentofscrews 21er thei'li'ke. "The rhead"plate" L M is` provided "with `the central opening-22 *through Whiclr/the'fiame-ofltheburning gases discharge.

' `iverlying` the'head'plate19istthe air deflector p1ate'23. `rIhis deectorplateis fany overall diameteriapproximate- `ly equallingtheinside":diameter Aofgthe* housing A'10 so that 'ittforms a horizontalpartitionirvthey housing above fthe pot burner and it ,is secured-finplace by-'means V"otithe "long*bolts'itwhichpass down' through the fdeectoi plate, between'theewallot fthe housing' Y16 and the Ywa ll'c ,fthe A-p'ot burnerto-ibefsecured in-the-bottom-of-the housing yas' illustrated. `--`In- -additionytheshorter bolts 'VZSare employed ortdirectly coupling the "deector-tplate 23'wi-th fthe head platev 19.

Y"The air1 deiiectorplate'12?,Y which is maintained above "and inl spaced rela-tion' with f the f headplate -ortopjplate #195- `bytheintegral depending lugs;` 26,- is pa'rtioularly'f'described and claimed inY my co-pending Lapplication "filed Marc-H524, l'-953,"iSe1"iail No5-344',353. iThiseplate hasthe 'central opening y'T27 which is 'concentricfwith i the-f opening arid which eis @defined fbyca 'dependin g @lip 28' which lfune/tions, as set forth '"in `the /co-pend-ingiapplication iabove referredito, ytodelect 'air-'owifng inwardly 'between'the plates-319mm@downwardly-and inwardly toward the fcenterfofthe pot.

T'IheJconstfruction of 1the-fpan-or xrecep,tac'lepertion"13l of thelpotfis also particularly seta/.forth and Lclaimed in-Ia rcopending eapplication lledffof-A even date herewithand this Lp'anfhas f azcentral-body C28 inthe formief :an upstanding `mound1lhavingithe:outwardly andi .downwardly sloping-top 'rand side surfaces maud lbfby-means1of W-hichioil'fbowing fiuithroughfithe Ladniission portl'29, liis causedito move out wa/idlyfandfradially'on; the bottom v wall 14` of'.4 theA ipot. ih'isportlYlSl exltends upwardiiyfthroughfthe 'axial L.center :oflthe moundZSiandshas Jthe.'fuel-supply pipe @connected with thelower end whereof. i

Theafinterioriof the pipefil is-ithreadeduor.smeothirto receive the :threaded Lorsirioofth #lower .end portion io'f a nod lwhich tis'tilattenediionitwo.sides.soasto permita fiireez'iiowfofiuel into the burner. Thisrod/functionsas /ai'pre-heating element, extending; @upwardly 4:an substantial -distance into then-burner :and oonductingheat :fromtthe'in- :iterior` of the burner down intother'inwardlyowingcoiL 1 'Rhei {t'opv surface lof ithe lbottomV Awall 14' Aoffthe pottr reiaeptaele l13uslopesrrloiavnuiardly4 andffoutwardly: from .the mound '28 ,asfshownnand fthe mound'is kencircled #by 1.a number of concentrici ibrolcen: rings 32 vwhich are 'in'zturn enclosed in an :outer continuous'. :annular ring or-wali`t33.

By reasoniof :the'outwardlyanddownwardly sloping Itop surface of theifhottomwallwMfandrmhe:sloping sur- :faeesza andfb.- ofuthe-cmound 28 lthefuelssoil :entering through the port 29 is maintained in constant movement .outwardly froml ,the Kentrancepoint.and; as. set-,forth in .my .co-.pending application vthis-:constant Amovementof i `the fueloil overtthe4 thick .cast metal bottom which .1ai`=ter a ,short period ot operation of `thev .burner becomes.highl;l heated,- causesthe 'oil kto he 'thoroughly vaporized: and v'cracked and thus'becomes fully Aconsumed and converted tocombust'iblegases. 'This action fof cracking the 1-s also obtained by the radiant heat which is directed downoil.

In accordance with the present invention by means of which a low tire or pilot tire can be maintained within the pot there is provided the central pilot burner which is generally designated 34. This pilot burner comprises a bottom ring 35 and a top ring 36 which are maintained in vertically spaced relation by the spaced inner and outer walls 37 and 38 respectively.

As shown particularly in Figure 3 the bottom ring has a central opening defined by an upwardly tapering wall 39 so that the bottom edge of the bottom ring isrelatively thin. The diameter of the bottom ring 35 is such as to permit the ring to be placed within the smallest one or the innermost one of the broken rings 32 as shown in Figure l and the inside diameter of the upwardly converging passage through the ring 35 is such as to encircle or enclose the mound 28 but not contact the latter as shown in Figure l. Thus an ample amount of space is provided between the inclined wall 39 and the mound 28 for the movement of gases and fuel oil across the top of the mound downwardly and outwardly toward the bottom edge of the ring 35.

The bottom edge of the ring 35 is, as shown in Figures 2 and 3, provided with a plurality of radially extending notches or channels 40 which permit the fuel oil to tlow out freely beneath the bottom edge of the pilot burner unit. Certain of these channels as, for example, the four designated 40a are slightly larger than the others to permit the free passage of gases and igniting flame from within the pilot burner outwardly to ignite fuel oil distributed between the rings 32 and 33 when it is desired to raise the tire in the burner.

The top ring 36 of the pilot burner is also provided with a central opening which is of considerably smaller diameter than the opening in the bottom ring 35 and which has the upwardly and outwardly aring wall 41.

The inner vertical and annular or circular wall 37 of the pilot burner is provided with a plurality of air passages or openings 42 and, as shown, the two walls 37 and 38, being in spaced relation and fixed to the top and bottom rings 35 and 36, provide a circular air chamber 43 which is supplied with air under pressure through the tube 44. One end of the tube 44 opens through the outer wall 38 of the pilot burner as shown and the other end extends above the thick wall of the pot receptacle and opens through the thinner wall 16 thereof as shown in Figure l. Accordingly it will be readily understood that the air under static pressure in the space between the wall 16 and the wall of the casing 10, will be fed downwardly through the tube 44 into the chamber 43 for discharge into the central part of the pilot burner.

When the pilot burner is operating the fuel oil will run in, in a very small amount, onto the top and side surfaces a and b of the mound 28 and burn within the chamber defined by the wall 37 andthe wall 39 of the bottom ring, being supplied with the necessary combustion air through the openings 42. When the inflowing fuel oil is admitted slowly or in small quantity all of the oil will be consumed within the pilot burner but when it becomes necessary to increase the activity of the pot burner the oil ow may be increased so that some of it will escape outwardly through the passages 40 and 40a. In this case the ame will under normal conditions follow through the bottom edge passages or notches and ignite the fuel within the pot receptacle outside the pilot burner.

In order to insure the ignition of the fuel oil outside the pilot burner when it is desired to operate the burner on high re there may be provided an asbestos wick 45. This wick is positioned so as to have one end extended across the top of the pilot burner or into the opening 41 as shown, from which it extends outwardly and downwardly along the side of the pilot burner and then outwardly over the rings 32 to the outermost continuous or unbroken ring 33. By the employment of this wick, when the burner is turned up, if the oil should not ignite immediately it will puddle in the outermost ring 33 and the wick will become quickly saturated and ignited at its top end from the low burning ame within the pilot burner. This flame will then be conducted to the outer or lower end of the wick which is in the oil outside the pilot burner and by this means the oil will be readily ignited.

With the construction herein described it is possible to obtain a low burning pilot which will crack all types of oil such as critical oils, run of the mine oils, diesel oil and the like. By the novel construction or formation of the device, there is provided the more or less restricted top opening in the ring 36, and there is provided the air admission holes 42 in the necessary number to admit the correct amount of air so that upon turning up the fuel supply for a high lire, the added volume of gases produced cannot escape with suicient rapidity through the top opening and as a result of the increased pressure set up within the pilot burner the re therein will go down and pass out through the passages 40 and 40a to ignite the fuel oil flowing into the larger burner, as above stated. The medium or high tire activity of the burner is obtained by the setting of the control valve by means of which the ow of oil is regulated. The pilot tube will then be operating under a ooded condition caused by the oil level increasing to an extent suiiicient to close the outlet passages or channels 40 and accordingly the gases from the burning fuel all have to pass out through the top opening of the pilot unit or tube and the flame from the pilot unit or tube is then sucked up into the flame of the medium or high re operating in the pot burner, the rising gases ceasing to be ignited within the pilot tube. On medium or high fire, therefore, the fuel gases burn above the pilot tube within the larger chamber of the main burner.

I claim:

1. A pot type oil burner comprising the combination of a main combustion chamber defined by bottom and side walls, a vertically disposed oil inlet port located centrally of said bottom wall and extending therethrough and a pilot burner comprising a lower ring supported by its lower edge on said bottom wall and concentric with said oil inlet port, an outer cylindrical sleeve supported on said ring, an inner cylindrical sleeve supported on said ring and concentric with said outer sleeve, a plurality of apertures in said inner sleeve, an upper ring carried by said inner and outer sleeves and closing the opening therebetween to provide an annular air chamber, said upper ring having a vertically disposed burner opening concentric with said inlet port and of less diameter than said inner sleeve, a forced draft tube communicating with said air chamber and extending substantially radially thereof exteriorly of said combustion chamber, a rod extending into said inlet port a substantial distance and through said burner opening in concentric relation thereto and a plurality of radially disposed grooves in the lower edge of said lower ring whereby upon a limited flow of oil to said inlet port and the flow of air through said tube to said air chamber and through said apertures said pilot burner will burn with a low flame and maintain said rod at a relatively high temperature to preheat said oil and burn any carbon deposit tending to form in said inlet port and upon increasing the ow of oil in excess of that burnable in said pilot burner said excess oil will ow outwardly through said grooves and the reduced burner opening in said upper ring will force flame outwardly through said grooves to ignite said excess oil in said main combustion chamber.

2. A pot type oil burner comprising the combination of a main combustion chamber deiined by bottom and side walls, a vertically disposed oil inlet por-t located centrally of said bottom wall and extending therethrough and a pilot burner comprising a lower ring supported by its lower edge on said bottom wall and concentric with said oil inlet port, an outer cylindrical sleeve supported on said ring, an inner cylindrical sleeve supported on said ring and concentric with said outer sleeve, a plurality of apertures in said inner sleeve, an upper ring carried by said inner and outer sleeves and closing the opening therebetween -to provide an annular air chamber, said upper ring having a vertically disposed burner opening concentric with said inlet port and of less diameter `than said inner sleeve, a forced draft tube communicating with said air chamber and extending exteriorly of said main combustion chamber, a rod extending into said inlet port and through said burner opening in concentric relation thereto and a plurality of groves in the lower edge of said lower ring whereby upon a limited flow of oil to said inlet port and the flow of air through said tube to said air chamber and through said apertures said pilot burner will burn with a low flame and maintain said rod at a relatively high temperature to preheat said oil and burn any carbon deposit tending to form in said inlet port and upon increasing the flow of oil in excess of that burnable in said pilot burner said excess oil will :dow outwardly through said grooves and reduced burner opening in said upper ring will force flame outwardly through said grooves to ignite said excess oil in said main combustion chamber.

3. A pot type oil burner comprising the combination of a main combustion chamber defined by bottom and side walls, a vertically disposed oil inlet port located centrally of said bottom wall and extending therethrough and a pilot burner supported on said bottom wall and concentric with said oil inlet port and comprising an outer cylindrical sleeve and an inner cylindrical sleeve concentric with said outer sleeve, a plurality of apertures in said inner sleeve, means at the upper ends of said sleeves closing the opening therebetween to provide an annular air chamber, said means having a vertically disposed burner opening concentric with said inlet port and of less diameter than said inner sleeve, a draft tube communicating with said air chamber and extending exteriorly of said main combustion chamber, a rod extending into said inlet port and through said burner opening in concentric relation thereto and a plurali-ty of openings in said pilot burner adjacent said bottom wall whereby upon a limited flow of oil-to said inlet port and the ow of air through said tube to said air chamber and through said apertures said pilot burner will burn with a low flame and maintain said rod at a relatively high temperature to preheat said oil and burn any carbon deposit tending to form in said inlet port and upon increasing the flow of oil in excess of that burnable in said pilot burner said excess oil will flow outwardly through said openings and the reduced burner opening in said means will force llame outwardly through said openings to ignite said excess oil in said main combustion chamber.

References Cited in the lile of this patent UNITED STATES PATENTS 2,293,697 Chadwick Aug. 25, 1942 2,513,551 Custance July 4, 1950 2,549,068 Donley Apr. 7, 1951 2,579,370 Donley Dec. 1,8, 1951 

